Wireless powering and bidirectional telemetry front-end for implantable biomedical devices

Wireless powering to implantable biomedical devices is highly desirable due to obviation of batteries or piercing wirings. This paper presents an implantable inductively powered front-end operating at 13.56MHz carrier frequency for biomedical applications, with the capabilities of power transfer, clock extraction and bidirectional command/data communication. The system consideration including the inductive coupling and the circuit building blocks of power management are given and high efficiency is highlighted as well. The ASIC has been fabricated in 0.18μm CMOS process. The rectifier achieves an efficiency of 66% and the ASK-demodulated command, extracted clock and LSK back-telemetry are verified through measurement. This design can be applied to diverse implantable biomedical applications where wireless powering is needed.